Forging



Feb. 24, 1942. c. P. BYRNES FORGING Filed July 27, 1939 M m wm INVENTOR llll lll' Patented Feb. 24, 1942 lJNlTED STATES PATENT OFFICE FORGING Clarence P. Byrncs, Delray Beach, Fla. Application July 27, 1939, Serial No. 286,847

4 Claims. (Q1. 29-4482) My invention relates to the manufacture of forgings and especially to forgings, such as axles, made by clamping a blank in'matrix dies and expanding one or both end portions such as shown in United States Patent No.761,778 to C. Mercader, of June 7, 1904; and is designed to overcome. difficulties which prevented commercial use of such a system.

' It was found in actual operation of such a system that the punch would diverge from the blank during its penetration, and could not be kept centered in the heated end portion of the blank; and consequently the walls of such end portions were non-uniform and varied in thickness.

I have found that by rotating the blank in one direction during the punching and expanding operation and rotating the punch in the opposite direction, preferably at about the same speed or class of speed, the punch will be kept centered and the Walls of the hollow ends kept substantially uniform in thickness around the circumference of the expanded portion.

In the drawing which shows somewhat diagrammatically one form of apparatus for carry- 7 ing half cavities shaped for axle forging and may have small serrations to grip the blank, and I clamp between them the central and end portions of a cylindrical blank 4, which end portions have been heated to forging temperature and the scale removed. The dies are preferably interfitting half octagons externally, and fit within corre sponding half clamps 5 and 6 of a cage having exterior surfaces which are circular in cross section though of different sizes.

Bearings I therefor are provided in stationary ringgear. IE} is mounted for sliding endwise'movement into and outof engagement with the teeth of the clamping sleeve, and is shifted to allow the split sleeve and dies to be removed. The punches or mandrels [4 are forced in by hydraulic cylinders or other suitable means and preferably have hollow steel or iron caps Ma fitting over their reduced end portions, the cap being slightly larger than the punch or plunger so that it projects slightly 'where its end abuts the shoulder of the plunger as disclosed in Patent 761,778. The

punch I4 is carried by a plunger 15 of a suitable hydraulic cylinder. The plunger is mounted in the bore of a rotary sleeve Hi, the plunger being keyed to the sleeve forrotary movement therewith and which keyed connection also provides for movement of the plunger through the bore axially. The sleeve is journaled in a fixed housing or bearing and has gear teeth I! meshing with a drive pinion 18. In using these plungers, the removable steel cap portions are forced into the end cavities formed in punching and remain at their inner ends when the punches are withdrawn. This reduces the heating and liability to distortion of the punches.

In using the apparatus, the ring gear is retracted and the upper halves 5 and 8 are removed or swung back as well as upper die 2. The heated blank with scale removed is inserted in the lower die 3 and then the upper die is dropped in place and over it the half cage or sleeve 5. The upper holder half with its half bearings is then lowered and the holder forced to closed position and if desired clamped. The ring gear is then moved in and rotated and the punches are rotated in the opposite direction to that of the hot blank ends, and forced home. The hot metal is expanded within the wheel seat portions and adjacent parts of the die cavities and during the last of the strokes the metal may flow back to fill up the end portions of the cavities against the collars l9 around the rear ends of the punches. The upper holder half 8, the upper clamp half 5, and the upper die 2 are lifted off and the rough axle removed, the punches being pulled back and the ring gear moved apart.

The advantages of the invention result from the reverse rotations of the blank and punches,

which aid in holding the punch control during its punching action; especially if the rotations are at about the same speed or R. P. M.s. A simple, cheap, and rapid method of and means for forging articles of varying cross section are thus provided.

The system may be used in forging seamless tube blanks as in Patent 717,886, the punching may be at one or both ends, and the apparatus may be widely varied without departing from my invention.

I claim:

1. In the method of forming a forging having within its end portion a hole of greater length than diameter, the steps consisting of rotating a relatively larger blank and a relatively smaller punch in opposite directions, simultaneously causing relative endwise movement of the blank and punch to force the punch into the end portion of the blank and expand it while forming a substantially straight hole therein, and then reversing the movement to cause withdrawal of the punch from the hole.

2. In the method of forming a forging having a longitudinal hole within its end portion, the steps consisting of rotating a relatively larger blank and a relatively smaller punch in opposite directions at about the same class of speed, and simultaneously causing relative endwise movement of the blank and punch to force the punch into the end portion of the blank and expand it while forming a substantially straight hole therein.

3. In the method of forming a forging having within its end portion a hole of greater length than diameter, the steps consisting of placing within a matrix die a blank having a relatively larger end portion, rotating the blank in one direction, causing relative movement between the blank and a relatively smaller punch to force the punch into the larger end portion of the blank and expand it, and simultaneously rotating the punch in the opposite direction to that of the blank at a speed suflicient to form a straight hole in the blank of greater length than diameter, and then separating the blank and die.

4. In the manufacture of forgings, the steps consisting of placing a blank within open-end matrix dies, forcing punches into opposite ends of the blank, during punching, rotating the blank in one direction and the punches in an opposite direction to that of the blank at about the same speed as that of the blank and thereafter removing the blank from the dies.

CLARENCE P. BYRNES. 

